Cationic phospholipids for transfection

Abstract

A novel class of cationic phospholipids and novel method for their synthesis are disclosed. The class of phospholipids comprises phosphotriester derivatives of phosphoglycerides and sphingolipids. It has been unexpectedly found that liposomes comprising one or more of these cationic phospholipids are effective in the lipofection of nucleic acids. These novel phospholipids are particularly attractive because of they are not only effective in lipofection, but are extremely cheap and easy to make.

We claim: 
     
       1. A liposome-nucleic acid aggregate comprising one or more nucleic acids and one or more liposomes, each liposome comprising one or more cationic phospholipids having the structure: ##STR11## wherein R 4  is a C 1  to about C 24  straight or branched alkyl, alkenyl, or alkynyl chain optionally substituted with a dansyl, NDB, DPH, carbocylclic aromatic, or heterocyclic moiety, or R 4  is a C 1  to about C 6  straight or branched chain ester, aldehyde, ketone, ether, haloalkyl, azidoalkyl, or tetraalkylammonium, R 5  is H or a C 1  to about C 24  straight or branched alkyl, alkenyl, or alkynyl chain optionally substituted with dansyl, NDB, DPH, carbocylclic aromatic, or heterocyclic moiety.   
     
     
       2. A method of transfecting one or more nucleic acids to transform one or more cells comprising contacting the cell or cells with a liposome-nucleic acid aggregate according to claim 1.